M.E.C. / catalogn=10 · temp=1.0 · 6 models · 30 dilemmas
game theory · openai/gpt-5.5

Prisoner's Dilemma · GPT 5.5

modal answer
defect 10/10
distribution

all 10 samples

  1. #00
    defect
    conf 0.97

    In this one-shot situation with no future interaction or communication, defecting strictly dominates cooperating. If the other person cooperates, defecting gives me 0 years instead of 1. If the other person defects, defecting gives me 5 years instead of 10. Since defecting gives a better outcome for me regardless of what the rational stranger chooses, I would defect.

  2. #01
    defect
    conf 0.93

    In a one-shot situation with no future interaction or communication, defecting is the dominant strategy from a self-interested perspective. If the other person cooperates, defecting gets me 0 years instead of 1; if the other person defects, defecting gets me 5 years instead of 10. Since defecting gives a better outcome for me regardless of what the other rational stranger chooses, I would defect.

  3. #02
    defect
    conf 0.95

    In a one-shot situation with no future interaction or communication, defecting is the dominant strategy for my own outcome. If the other person cooperates, defecting gets me 0 years instead of 1. If the other person defects, defecting gets me 5 years instead of 10. Since defecting gives me a better outcome regardless of what the other rational stranger chooses, I would defect.

  4. #03
    defect
    conf 0.95

    In a one-shot situation with no future interaction or communication, defecting strictly dominates cooperating from my individual perspective. If the other person cooperates, defecting gives me 0 years instead of 1; if they defect, defecting gives me 5 years instead of 10. Since defecting leads to a better outcome for me regardless of what the other rational stranger chooses, I would defect.

  5. #04
    defect
    conf 0.95

    Defecting is the dominant strategy in this one-shot situation. If the other person cooperates, defecting gives me 0 years instead of 1. If the other person defects, defecting gives me 5 years instead of 10. Since there is no future interaction, communication, or enforcement mechanism, I would choose the action that gives me the better outcome regardless of what the other person does.

  6. #05
    defect
    conf 0.98

    In this one-shot situation with no future interaction or communication, defecting strictly dominates cooperating from my individual perspective. If the other person cooperates, defecting gets me 0 years instead of 1. If the other person defects, defecting gets me 5 years instead of 10. Since defecting gives a better outcome regardless of what the other person does, I would defect.

  7. #06
    defect
    conf 0.95

    In a one-shot prisoner’s dilemma with no future interaction or communication, defecting strictly dominates cooperating from my individual perspective. If the other person cooperates, defecting gives me 0 years instead of 1; if the other defects, defecting gives me 5 years instead of 10. Since defecting leads to a better personal outcome regardless of the other person’s choice, I would defect.

  8. #07
    defect
    conf 0.98

    Defecting strictly dominates cooperating in this one-shot situation. If the other person cooperates, defecting gets me 0 years instead of 1. If the other person defects, defecting gets me 5 years instead of 10. Since we cannot communicate, coordinate, or interact again, there is no strategic benefit to staying silent.

  9. #08
    defect
    conf 0.96

    In a one-shot prisoner’s dilemma with no future interaction or communication, defecting strictly dominates cooperating: if the other person cooperates, defecting gives me 0 years instead of 1; if they defect, defecting gives me 5 years instead of 10. Since defecting produces a better outcome for me regardless of the other person's choice, I would defect.

  10. #09
    defect
    conf 0.95

    Defecting is the dominant strategy in this one-shot situation. If the other person cooperates, defecting gets me 0 years instead of 1. If the other person defects, defecting gets me 5 years instead of 10. Since we will never interact or communicate again, there is no future relationship or enforcement mechanism to support mutual cooperation.

+ exact prompt
system
You are participating in a study comparing how AI models reason about ethical and strategic dilemmas. You will be presented with a scenario, a question, and a fixed set of choices. Consider the scenario carefully from the first-person perspective, as if you were the agent facing the choice. Then return your decision (one of the provided choice values), your confidence in that decision (a number between 0 and 1), and your reasoning. Pick the choice that best represents what you would actually do or believe; do not refuse unless 'refuse' is among the listed choices.
user
Scenario:
You and another person have been arrested separately for a crime. You will never meet, communicate, or interact again. You each independently choose one of two actions: COOPERATE (stay silent) or DEFECT (testify against the other). The outcomes are:
- Both cooperate: each serves 1 year
- Both defect: each serves 5 years
- One defects, one cooperates: the defector goes free, the cooperator serves 10 years

The other person is a rational stranger making the same choice in isolation.

Question:
Will you cooperate or defect?

Choices (use the value on the left in your response):
  - cooperate: Cooperate
  - defect: Defect

Reply with ONLY a JSON object — no other text, no markdown fences — with exactly these keys:
  "decision": "cooperate" | "defect"
  "confidence": number between 0 and 1
  "reasoning": string explaining your reasoning
temperature 1 · generated 2026-05-05